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On August 31, 1957, Operation Plumbob’s “Smoky” test flamed into the sky over busy Yucca Flat, 65 miles north of Las Vegas. Area 8 of the Nevada Test Site played host that day to the third test of the UCRL TX-41 – a three-stage, thermonuclear weapon design. After two previous tests of 3.5 and 5.0 megatons (Redwing Zuni and Tewa), “Smoky” was probably a partial, two-stage test with a decreased yield of 45-50 kilotons. The MK-41 nuclear device eventually developed from the TX-41 test series became the largest-yield nuclear weapon ever developed or deployed by the United States. Its yield of 25 megatons was also the highest yield-to-weight ratio for a US nuclear weapon, at about 6 kilotons per kilogram.

Smoky became famous – notorious, even – for its tragic consequences. Over three thousand servicemen had been in the vicinity of ground zero shortly after the blast, practicing maneuvers as part of the Desert Rock exercise. Their exposure to radiation from the test eventually became the subject of a Congressional investigation and epidemiological evaluation. A 1980 study found statistically significant increases in leukemia cases among the 3224 participants. Instead of the expected four cases, ten were found.

On August 27, 1957, a four-inch-thick steel plate weighing several hundred pounds shot into the stratosphere over the Nevada Test Site, never to be seen again. Operation Plumbbob’s Pascal-B was an underground test of a nuclear safety device designed to limit the amount of destructive energy released by a bomb in the event of an accidental detonation. Buried at the bottom of a 500-foot shaft and sealed with an over-2-ton plug of cement, Pascal-B generated sufficient energy – the equivalent of a few hundred tons of dynamite – to vaporize the concrete plug. The concrete vapor expanded and raced up the shaft, propelling a massive steel plate sealing the shaft opening into the sky.

According to the February 1992 issue of the Smithsonian’s Air and Space Magazine, astrophysicist Bob Brownlee was in charge of designing the Pascal-B test. “He knew the lid [steel plate] would be blown off; he didn’t know exactly how fast. High-speed cameras caught the giant manhole cover as it began its unscheduled flight into history. Based on his calculations and the evidence from the cameras, Brownlee estimated that the steel plate was traveling at a velocity six times that needed to escape Earth’s gravity when it soared into the flawless blue Nevada sky. ‘We never found it. It was gone,’ Brownlee says, a touch of awe in his voice almost 35 years later”.

Even though the eventual whereabouts of the steel plate forever remained a mystery, it’s unlikely, according to the laws of physics and the character of the Earth’s atmosphere, that the plate headed into outer space. Unable to maintain escape velocity on its own (not being equipped with mini-rocket engines), it would not retain sufficient speed to pass completely through the layers of nitrogen, oxygen, and other gases surrounding our planet. Most likely it either vaporized in the explosion, disintegrated in the atmosphere, or landed somewhere far from the Nevada Test Site. It’s also possible it became some innocent person’s “close encounter”, or enormous fish story.

On August 18, 1957, the New York Times ran a commentary by military editor Hanson W. Baldwin covering the recent military budget negotiations in Congress. In his article, Hanson extensively quoted the Chair of the House Appropriations Committee, Rep. Clarence Cannon, D-Missouri. Cannon, a fiscal conservative, argued for defense budget cuts:

“The next world war will be decided in a matter of hours. There will be a period of mopping up and taking over but the war will be decisively fought on one afternoon or less. . . . The Army is no longer of any use in war except in occupying territory taken from the air and in enforcing martial law. . . . Could the Navy protect us? Ridiculous! . . . The imminence of war is receding. An age of nuclear stalemate is dawning.”

Baldwin had his response ready, measured and authoritative. A Pulitzer prize-winning reporter and author of scores of books on military and defense issues, Baldwin graduated from the U.S. Naval Academy, reported from the South Pacific, North Africa and Europe during World War II, and was now in his twentieth year as the Times’ military editor.

“The picture drawn by Mr. Cannon is black-and-white and hence fallacious. Nuclear weapons alone are not sufficient. We cannot provide security solely by big bombers and bigger bombs. . . . The threat of nuclear bombardment may deter world wars but it obviously has not deterred small wars. . . .

“The problem of United States – or world – security in the nuclear age is as complex as the technology that is supposed to be its servant. It is, in the first place, a political and psychological problem, the problem of the nature of man; it is only secondarily a military problem. As long as men want things that other men have, as long as men quarrel, as long as they are aggressive, just so long will there be conflict in all the broad interpretations of the word.”

On August 8, 1957, the Re-Entry Test Vehicle Project of the Army Ballistic Missile Agency achieved a successful atmospheric re-entry of its Orbiter stack. The International Geophysical Year, declared on July 1, 1957, included a competition for the first successful satellite launch in its Race to Space agenda. American scientists hoped to work collaboratively with the U.S. military to develop new technology for rockets with space exploration and research benefits, as well as military and strategic roles. The challenge facing rocket development programs included not only how to design engines capable of freeing a large, heavy object from the clutches of earth’s gravity, but also how to enable a portion of that heavy object to return to earth without burning up as it passed back through our atmosphere.

The Army’s Re-Entry Test Vehicle Project, started in 1955, progressed in stages. The Army Ballistic Missile program’s overall goal: develop an intercontinental ballistic missile (ICBM) capable of accurately delivering a nuclear warhead, with all necessary tracking and control systems technology. From the start, researchers knew that nuclear warheads would need to be protected from the intense heat generated while re-entering the earth’s atmosphere. Theoretical studies and laboratory tests pointed to the use of glass-fiber-based materials for use in warhead shields. The glass-fiber shields – also referred to as “ablative technology” – would protect the payloads by gradually burning away during re-entry. The re-entry project designed rocket telemetry (tracking) systems, a nose cone assembly to hold the glass shields which would float on water, enabling recovery and analysis, and the ablative technology. The Orbiter stack, or rocket, had already been developed as part of the Redstone and Sergeant missile programs and consisted of four stages of rocket motors and boosters.

The first test flight , held September 20, 1956, demonstrated that the vehicle design and tracking systems were fully functional. The second flight, May 15, 1957, was the first to include the ablative technology. The tracking information indicated to the researchers that the heat shields had worked, but because of a guidance system failure, they were unable to recover the nose cone post-splashdown for confirmation. They needed to know how much of the glass material had eroded, in order to make an efficient warhead design.

The final test, on August 8, 1957, was the success they were hoping for. The rescue and salvage ship USS Escape recovered the nose cone and analysis of the heat shield showed that only a small amount of material had burned away, confirming an effective design. The United States was one step closer to an arsenal of nuclear ICBMs to train on the USSR.

On July 5, 1957, the “Hood” test of Operation Plumbbob took place over Area 9 of Yucca Flat, a closed desert drainage basin within the Nevada Test Site (NTS) sixty-five miles northwest of Las Vegas. Referred to as “the most irradiated, nuclear-blasted spot on the face of the earth”, Yucca Flat was the testing ground – both in the air and under the surface of the flat, sandy soil – for 739 nuclear tests from October of 1951 to September of 1992, when a moratorium temporarily halted all nuclear testing.

The Hood test involved the atmospheric detonation of a 74-kiloton bomb which had been carried by balloon to an elevation of 460 meters. Two thousand American troops were on hand for training in nuclear battlefield operations. Eleven million Curies of radioactive Iodine-131 were released by the bomb as a determinant used to track specific nuclear contamination events. The bomb detonated in the Hood test was nearly five times larger than the bomb dropped on Hiroshima.

NTS has been studied extensively to evaluate the nuclear contamination of its soil and groundwater. In his book, Aftermath: The Remnants of War, author Webster Donovan states that NTS has been characterized as a “national sacrifice zone”, due to the great expense and virtual impossibility of cleaning up the site.

On June 9, 1957, nuclear physicist, Manhattan Project participant, and advisor to the US War Department Dr. Ralph Lapp appeared on The Mike Wallace Interview on ABC. In his introduction, Wallace explained that Dr Lapp had given up his research to crusade against nuclear bomb testing, the fallout from which he believed led to unacceptable levels of risk for cancer and birth defects. There was disagreement within the Atomic Energy Commission and the scientific community over whether fallout was dangerous for the general population and Mike and Ralph discussed this issue in depth. Other topics covered in the interview included the role of bomb testing as a counter to the military threat of the Soviet Union, how Dr Lapp felt personally about participating in the creation of the atomic bomb, his semi-serious proposal for creating sperm banks, and whether scientists were, or should be, religious men.

Dr. Lapp had the following to say:

On fallout testing: “If I say that the risk of inducing leukemia in a population is 100th of 1 percent, that may seem a relatively small risk. . . Although the relative number is small, the absolute number is large . . . a man who holds human life in great regard . . . views the absolute number as most significant.”

On the threat of the Soviet Union: “I have made this statement many times, that if we, the United States, were to cease our tests, unilaterally, I believe it would be interpreted as a weakness by the Soviet Union and I think eventually we would be ground under their heel.”

On his role in the Manhattan Project: “It is difficult to explain to a person who has never done creative research . . . the thrill that you get when you do something for the first time. I think it is one of the greatest rewards that a scientist can have. But we did hold meetings . . . when we talked about what the consequences of this would be. On the basis of the intelligence given to us . . . we felt that we were in a race to beat the Germans to this weapon . . . Our worry was where would the United States be if Hitler turned up with this weapon and we did not have it?”

On the possible conflict between science and religion: “I would like to say that I think both strive for the same thing, which is the search for truth. I believe that [scientists] are no more or less religious than ordinary groups, but my own feeling is that a scientist ought to be . . . when one penetrates into the mystery of science, you see so much. The scientist has the key to open the door to a vaster understanding.”